They have a right to. They just can’t stop people from doing certain things. The purpose of unionizing is to say “this company has been treating us unfairly and

They have a right to. They just can’t stop people from doing certain things. The purpose of unionizing is to say “this company has been treating us unfairly and we’re powerless to stop it. But together we could.” If Amazon was treating its employees fairly, they’d be less inclined to unionize.